Module
ActionController::ParameterEncoding::ClassMethods

Specify that a given action's parameters should all be encoded as
ASCII-8BIT (it “skips” the encoding default of UTF-8).

For example, a controller would use it like this:

class RepositoryController < ActionController::Base
skip_parameter_encoding :show
def show
@repo = Repository.find_by_filesystem_path params[:file_path]
# `repo_name` is guaranteed to be UTF-8, but was ASCII-8BIT, so
# tag it as such
@repo_name = params[:repo_name].force_encoding 'UTF-8'
end
def index
@repositories = Repository.all
end
end

The show action in the above controller would have all parameter values
encoded as ASCII-8BIT. This is useful in the case where an application must
handle data but encoding of the data is unknown, like file system data.